A risk score model of 30-day readmission in ulcerative colitis after colectomy or proctectomy.

INTRODUCTION: The Center for Medicare and Medicaid Services established 30-day readmission rate as a key metric in measuring high-value, cost-conscious care; therefore, our aim is to develop a risk score for 30-day readmission in ulcerative colitis (UC) patients undergoing colectomy or proctectomy.

METHODS: This study used data from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) participant user file (2011-2015). Patients with UC undergoing colectomy or proctectomy were identified using ICD-9, 10, and CPT codes. Stepwise multivariate analyses were used to determine risk factors associated with readmission including pre-operative conditions, laboratory results, operative variables, and post-operative complications. For readmission risk score assessment, a weighted logistic regression model was built and validated using ACS NSQIP 2011-2014 and 2015 data, respectively.

RESULTS: A total of 4797 patients were included with 963 (20%) patients readmitted within 30 days. Potentially modifiable risk factors included deep vein thrombosis, pulmonary embolism, renal insufficiency, wound infection, urinary tract infection, sepsis/septic shock, and pre-existing congestive heart failure. Ten percent of patients with a risk score between 0 and 9 were readmitted, 18.5% with a score between 10 and 19, 52.2% with a score between 20 and 29, and 59.6% in patients with a risk score >29.

CONCLUSIONS: Multiple potentially preventable risk factors are associated with 30-day readmission following colectomy or proctectomy in UC patients. Higher risk scores are associated with increased risk of unplanned readmission.